Since the driving properties of a tire, in particular a vehicle pneumatic tire, depend to a large extent on the rubber composition of the tread, particularly high demands are made on the composition of the tread compound. In recent years the overall level of driving properties has been raised by the partial or complete replacement of the filler carbon black by silicic acid in rubber compounds. However, the known conflicts of objectives of the conflicting tire properties also still persist with tread compounds containing silicic acid. As a rule an improvement in wet traction and dry braking thus still entails a deterioration in rolling resistance, winter properties and abrasion characteristics.
Many approaches have already been pursued to resolve these conflicts of objectives. Thus, for example, diverse, also modified polymers, resins, softeners and highly dispersed fillers for rubber compounds have been used and attempts have been made to influence the vulcanized material properties by modifying the compound production.
For example, tread compounds are known from EP-A-1 052 270 which contain, i.a., a liquid polymer, e.g., polybutadiene for a good grip on ice. Tread compounds are likewise known from DE 38 04 908 A1 that contain liquid polybutadiene for good winter properties. Liquid polybutadiene with a high vinyl content is also proposed in EP-A-1 035 164 for tire treads as a replacement for conventional processing oils. However, the use of liquid polybutadiene in conventional compounds has a very negative effect on the dry braking of tires.